Bridgeport Ballscrew Dilemma?

What is the lead on the screws? (1 turn = travel distance?)
DO NOT attempt to do ANY climb milling with manual ball screws.
I personally would convert back to CNC using a Centroid Acorn board, if that's not an option and the screw lead is not large, make new handles or handle adapters and leave the ball screws alone.

Both X and Y ball screws travel 0.200"/ turn. These have double nuts that pre-load the screws, which as I understand it provide some resistance to movement when milling. The preload can be adjusted by changing the width of the spacer between the nuts. I'm just a hobbyist so I may be incorrect about the latter statement.
 
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I think Wreck's idea of using any hand wheel that can fit with comfort and spending your time/money on a DRO is best by far.

No need to do what it takes to get back to stock wheels and graduated dials, will cost significant time/money. You could just file in a flat spot on the shaft and get a hand wheel with a set screw and be good to go with a DRO setup.

If you end up using it much you likely will want to go with the DRO anyway.

Also would leave the screw ends as they are in case you or a future owner wanted to return to CNC. Try to avoid cutting off length.

Up and cutting chips in a day. Could always return to 1) 2) or 3) later if you wanted to.
 
I'm beginning to warm up to the suggestion of leaving the screw lengths as they are. The Y screw sticks out a lot but I can probably learn to live with it. The mill came with a practically new Lyman power feed, which sits on the left side of the X axis. The gears don't quite match the screw length but I'm sure something can figured out.

The mill originally had an Acu-Rite DRO. Would it be advisable to use the same manufacturer for a replacement? The mounting holes would probably be the same for the X axis scale. The mounting bracket for the Y axis is still on the mill. I also have the original bracket and mounting for the monitor.
 
If you are replacing the DRO, then any manufacturer of your choice will do.
 
If you are replacing the DRO, then any manufacturer of your choice will do.

Would the mounting hole locations be the same for all manufacturers? If not, wouldn't it be easier to just use the one that originally was used?
 
I'm going to guess that the mountings would be different. There is a good chance that even from the same manufacturer the mounting would not be the same unless you got the exact model that was installed, even then there may be some differences.

I'm a real fan of magnetic scales. I have them on all of my machines.
 
I'm going to guess that the mountings would be different. There is a good chance that even from the same manufacturer the mounting would not be the same unless you got the exact model that was installed, even then there may be some differences.

I'm a real fan of magnetic scales. I have them on all of my machines.

Why magnetic scales?
 
They are very compact, bullet proof, and accurate.

Here is a picture of my X axis scale read head (just above the date stamp), you can just see the magnetic tape attached to the table.

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